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Chinese Journal of Aeronautics 2024年第5期37卷 180-198页

作者： Runfu LIU Zhenyao LI Huiliu ZHANG qixing wang Yue HUANG Yancheng YOU School of Aerospace Engineering Xiamen UniversityXiamen 361000China

The mixing effectiveness of the airflow between the inner and outer bypass inlets of a Rear Variable-Area Bypass Injector(RVABI)is the key to the afterburner performance of variable cycle engines.This paper describes an optimized RVABI design based on an alternating area regulator to improve the velocity/temperature uniformity of the incoming flow at the afterburner.Compared with a classical RVABI,numerical simulations show that the proposed alternating RVABI performs better in terms of thermal mixing efficiency and total pressure loss in different variable cycle engine modes.Both the increasing air contact area between the inner and outer bypass of alternating structure RVABI,and a larger streamwise vortex in the inner bypass inlet due to the proposed alternating lobe structure in the RVABI contribute to the significantly increase of mixing effectiveness.Besides,the alternating regulator induces strong streamwise vortex,which helps to improve the airflow mixing with its vortex-induced velocity.The interaction between the streamwise vortex and azimuthal vortex further promises the velocity/temperature uniformity after the RVABI.With the increase of alternating lobe’s height ratio,the covering area of the streamwise vortex and the azimuthal vortex is enlarged,which further enhances the thermal mixing efficiency of the RVABI.This design gives an insight into the future design and optimization of RVABI.

关键词： Alternating area regulator Lobed mixer Variable cycle engine Rear Variable-Area Bypass Injector(RVABI) Streamwise vortex

Performance Analysis of Sparse Array based Massive MIMO via Joint Convex Optimization

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China Communications 2022年第3期19卷 88-100页

作者： Mengting Lou Jing Jin Hanning wang Dan Wu Liang Xia qixing wang Yifei Yuan Jiangzhou wang Future Research Lab China Mobile Research InstituteBeijing 100053China School of Engineering and Digital Arts University of KentCanterburyU.K.

Massive multiple-input multiple-output(MIMO)technology enables higher data rate transmission in the future mobile communications.However,exploiting a large number of antenna elements at base station(BS)makes effective implementation of massive MIMO challenging,due to the size and weight limits of the masssive MIMO that are located on each BS.Therefore,in order to miniaturize the massive MIMO,it is crucial to reduce the number of antenna elements via effective methods such as sparse array synthesis.In this paper,a multiple-pattern synthesis is considered towards convex optimization(CO).The joint convex optimization(JCO)based synthesis is proposed to construct a codebook for beamforming.Then,a criterion containing multiple constraints is developed,in which the sparse array is required to fullfill all constraints.Finally,extensive evaluations are performed under realistic simulation settings.The results show that with the same number of antenna elements,sparse array using the proposed JCO-based synthesis outperforms not only the uniform array,but also the sparse array with the existing CO-based synthesis method.Furthermore,with a half of the number of antenna elements that on the uniform array,the performance of the JCO-based sparse array approaches to that of the uniform array.

关键词： B5G 6G sparse array joint convex optimization massive MIMO system-level simulation

Environment Information-Based Channel Prediction Method Assisted by Graph Neural Network

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China Communications 2022年第11期19卷 1-15页

作者： Yutong Sun Jianhua Zhang Yuxiang Zhang Li Yu qixing wang Guangyi Liu State Key Lab of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China Future Research Laboratory China Mobile Research InstituteBeijing 100053China

Recently,whether the channel prediction can be achieved in diverse communication scenarios by directly utilizing the environment information gained lots of attention due to the environment impacting the propagation characteristics of the wireless channel.This paper presents an environment information-based channel prediction(EICP)method for connecting the environment with the channel assisted by the graph neural networks(GNN).Firstly,the effective scatterers(ESs)producing paths and the primary scatterers(PSs)generating single propagation paths are detected by building the scatterercentered communication environment graphs(SCCEGs),which can simultaneously preserve the structure information and highlight the pending scatterer.The GNN-based classification model is implemented to distinguish ESs and PSs from other scatterers.Secondly,large-scale parameters(LSP)and small-scale parameters(SSP)are predicted by employing the GNNs with multi-target architecture and the graphs of detected ESs and PSs.Simulation results show that the average normalized mean squared error(NMSE)of LSP and SSP predictions are 0.12 and 0.008,which outperforms the methods of linear data learning.

关键词： channel prediction propagation environment graph scatterer detection GNN

Porous framework materials for energy&environment relevant applications:A systematic review

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Green Energy & Environment 2024年第2期9卷 217-310页

作者： Yutao Liu Liyu Chen Lifeng Yang Tianhao Lan Hui wang Chenghong Hu Xue Han qixing Liu Jianfa Chen Zeming Feng Xili Cui Qianrong Fang Hailong wang Libo Li Yingwei Li Huabin Xing Sihai Yang Dan Zhao Jinping Li College of Chemical Engineering and Technology Shanxi Key Laboratory of Gas Energy Efficient and Clean UtilizationTaiyuan University of TechnologyTaiyuan030024China School of Chemistry and Chemical Engineering South China University of TechnologyGuangzhou510640China Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China Department of Chemistry The University of ManchesterManchesterM139PLUK Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou311215China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun130012China Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials Department of ChemistryUniversity of Science and Technology BeijingBeijing100083China

Carbon peaking and carbon neutralization trigger a technical revolution in energy&environment related fields.Development of new technologies for green energy production and storage,industrial energy saving and efficiency reinforcement,carbon capture,and pollutant gas treatment is in highly imperious demand.The emerging porous framework materials such as metal–organic frameworks(MOFs),covalent organic frameworks(COFs)and hydrogen-bonded organic frameworks(HOFs),owing to the permanent porosity,tremendous specific surface area,designable structure and customizable functionality,have shown great potential in major energy-consuming industrial processes,including sustainable energy gas catalytic conversion,energy-efficient industrial gas separation and storage.Herein,this manuscript presents a systematic review of porous framework materials for global and comprehensive energy&environment related applications,from a macroscopic and application perspective.

关键词： Porous framework materials Catalysis Separation Gas storage Carbon neutrality

A Predictive 6G Network with Environment Sensing Enhancement:From Radio Wave Propagation Perspective

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China Communications 2022年第6期19卷 105-122页

作者： Gaofeng Nie Jianhua Zhang Yuxiang Zhang Li Yu Zhen Zhang Yutong Sun Lei Tian qixing wang Liang Xia State Key Laboratory of Networking and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China Future Research Laboratory China Mobile Research InstituteBeijing 100053China

In order to support the future digital society,sixth generation(6G)network faces the challenge to work efficiently and flexibly in a wider range of scenarios.The traditional way of system design is to sequentially get the electromagnetic wave propagation model of typical scenarios firstly and then do the network design by simulation offline,which obviously leads to a 6G network lacking of adaptation to dynamic environments.Recently,with the aid of sensing enhancement,more environment information can be obtained.Based on this,from radio wave propagation perspective,we propose a predictive 6G network with environment sensing enhancement,the electromagnetic wave propagation characteristics prediction enabled network(EWave Net),to further release the potential of 6G.To this end,a prediction plane is created to sense,predict and utilize the physical environment information in EWave Net to realize the electromagnetic wave propagation characteristics prediction timely.A two-level closed feedback workflow is also designed to enhance the sensing and prediction ability for EWave Net.Several promising application cases of EWave Net are analyzed and the open issues to achieve this goal are addressed finally.

关键词： 6G network electromagnetic waves propagation characteristics prediction environment information sensing enhancement

Full-spectrum cell-free RAN for 6G systems: system design and experimental results

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Science China(Information Sciences) 2023年第3期66卷 80-93页

作者： Dongming wang Xiaohu YOU Yongming HUANG Wei XU Jiamin LI Pengcheng ZHU Yanxiang JIANG Yang CAO Xinjiang XIA Ziyang ZHANG Qingji JIANG Pan wang Dongjie LIU Kang ZHENG Mengting LOU Jing JIN qixing wang Jiangzhou wang National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories China Mobile Research Institute School of Engineering University of Kent

With distributed transceivers and scalable cooperative transmission, cell-free massive multipleinput multiple-output(CF-m MIMO) technology eliminates the “cells” of traditional mobile communications,thereby significantly improving the performance of wireless networks. CF-m MIMO is considered as a major technical tool for achieving the key performance indicators of sixth generation(6G) mobile communication systems. In this paper, a scalable implementation architecture for CF-m MIMO is proposed, based on which potential key technologies such as channel information acquisition, transceiver design, dynamic user and access point association, and novel duplexing are introduced. Finally, based on low-cost commercial access points, a CF-m MIMO testbed with 64 transmit and receive antennas is developed, and the performance of the distributed receiver design is evaluated.

关键词： 6G scalable cell-free massive MIMO cell-free radio access network prototype system

5G Features from Operation Perspective and Fundamental Performance Validation by Field Trial

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China Communications 2018年第11期15卷 33-50页

作者： Guangyi Liu Yuhong Huang Fei wang Jianjun Liu qixing wang China Mobile Research Institute Beijing 100053 China

The fast deployment and penetration of 4 G has cultivated human behaviors on mobile data consumption, leading to explosive growth in mobile traffic and stimulating new requirements on the capabilities of mobile networks. To meet the requirements of mobile networks toward year 2020, the next generation of mobile networks(termed as IMT-2020, or 5 G) is designed to support 100 Mbps–1 Gbps user-experienced data rate, 1 ms radio transmission latency, and 1 million connections per square kilometer. Recalling the vision and requirements of 5 G targeting for commercial launch in 2020, this article overviews the key features of 5 G and compares with those of 4 G, and reports the world first field trials conducted to validate the key performance of 5 G radio interface in 3.5 GHz band. The trial results show that a 1 ms transmission latency and 1 Gbps data rate are achievable.

关键词：试用表演操作特征活动网络 Gbps 人的行为数据率

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海-陆交互作用与海岸带碳中和农业驱动

农业环境科学学报 2024年第1期43卷 1-10页

作者：周启星王辉欧阳少虎南开大学环境科学与工程学院/南开大学碳中和交叉科学中心环境污染过程与基准教育部重点实验室天津300350

海岸带既是生态脆弱区也是低碳农业发展“前哨”。推动和发展碳中和农业符合时代所需,也符合绿色、可持续发展理念。基于此,本文阐述了在海岸带区域发展碳中和农业的相关问题和重要性。首先,本文阐释了海陆交互作用以及海岸带碳中和农... 详细信息

海岸带既是生态脆弱区也是低碳农业发展“前哨”。推动和发展碳中和农业符合时代所需,也符合绿色、可持续发展理念。基于此,本文阐述了在海岸带区域发展碳中和农业的相关问题和重要性。首先,本文阐释了海陆交互作用以及海岸带碳中和农业发展理念;然后,分析了海岸带碳中和农业驱动中的碳中和农业生物、人工光合作用与农业驱动以及该理念的工程化应用问题;最后,深入剖析了如何识别海岸带农业核心碳汇,包括原位监测、同位素标记与统计学分析方法,并在此基础上提出了农业碳汇增强技术,为后续海岸带碳中和农业的构建、发展和实践提供参考,同时对促进脆弱的海岸带生态系统的保护和绿色低碳农业的发展具有重要意义。

关键词：碳中和农业海岸带海陆交互作用可持续发展人工光合作用

Vision,Requirements and Network Architecture of 6G Mobile Network beyond 2030

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China Communications 2020年第9期17卷 92-104页

作者： Guangyi Liu Yuhong Huang Na Li Jing Dong Jing Jin qixing wang Nan Li China Mobile Research Institute Beijing 100053China

With the 5th Generation(5G)Mobile network being rolled out gradually in 2019,the research for the next generation mobile network has been started and targeted for 2030.To pave the way for the development of the 6th Generation(6G)mobile network,the vision and requirements should be identified first for the potential key technology identification and comprehensive system design.This article first identifies the vision of the society development towards 2030 and the new application scenarios for mobile communication,and then the key performance requirements are derived from the service and application perspective.Taken into account the convergence of information technology,communication technology and big data technology,a logical mobile network architecture is proposed to resolve the lessons from 5G network design.To compromise among the cost,capability and flexibility of the network,the features of the 6G mobile network are proposed based on the latest progress and applications of the relevant fields,namely,on-demand fulfillment,lite network,soft network,native AI and native security.Ultimately,the intent of this article is to serve as a basis for stimulating more promising research on 6G.

关键词： 6G vision and scenarios network performance indicators network features

Power allocation for collaborative transmission in LTE-Advanced

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Frontiers of Electrical and Electronic Engineering in China 2011年第4期6卷 515-520页

作者： Jing JIN Chongsheng LIN qixing wang Hongwen YANG Yafeng wang Wireless Theories and Technologies Lab(WT&T) Beijing University of Posts and TelecommunicationsBeijing 100876China China Mobile Research Institute Beijing 100053China

Collaborative transmission among evolved Node-Bs(eNBs)is one of the promising techniques for LTE-Advanced to provide broader coverage and higher spectral efficiency.The interference among multi-cell transmission can be mitigated by joint precoding,such as multi-cell block diagonalization(BD)at cooperative eNBs.The major difference between multi-cell and single-cell transmission is that the power constraint has to be considered on a per-eNB basis.To satisfy per-eNB power constraint(PePC),a simplified power allocation algorithm for the multi-cell BD based collaborative transmission is proposed in this paper.The algorithm provides a power allocation coefficient matrix for BD to meet PePC.Simulation results demonstrate that the proposed algorithm has a near-optimal performance with simplicity.

关键词： LTE-Advanced coordinated transmission per-eNB power constraint(PePC) block diagonalization(BD)